<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Cache
 * @subpackage Zend_Cache_Frontend
 * @copyright  Copyright (c) 2005-2011 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: File.php 24218 2011-07-10 01:22:58Z ramon $
 */

/**
 * @see Zend_Cache_Core
 */
require_once 'Zend/Cache/Core.php';

/**
 * @package    Zend_Cache
 * @subpackage Zend_Cache_Frontend
 * @copyright  Copyright (c) 2005-2011 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Cache_Frontend_File extends Zend_Cache_Core {
	
	/**
	 * Consts for master_files_mode
	 */
	const MODE_AND = 'AND';
	const MODE_OR = 'OR';
	
	/**
	 * Available options
	 *
	 * ====> (string) master_file :
	 * - a complete path of the master file
	 * - deprecated (see master_files)
	 *
	 * ====> (array) master_files :
	 * - an array of complete path of master files
	 * - this option has to be set !
	 *
	 * ====> (string) master_files_mode :
	 * - Zend_Cache_Frontend_File::MODE_AND or Zend_Cache_Frontend_File::MODE_OR
	 * - if MODE_AND, then all master files have to be touched to get a cache invalidation
	 * - if MODE_OR (default), then a single touched master file is enough to get a cache invalidation
	 *
	 * ====> (boolean) ignore_missing_master_files
	 * - if set to true, missing master files are ignored silently
	 * - if set to false (default), an exception is thrown if there is a missing master file
	 * @var array available options
	 */
	protected $_specificOptions = array ('master_file' => null, 'master_files' => null, 'master_files_mode' => 'OR', 'ignore_missing_master_files' => false );
	
	/**
	 * Master file mtimes
	 *
	 * Array of int
	 *
	 * @var array
	 */
	private $_masterFile_mtimes = null;
	
	/**
	 * Constructor
	 *
	 * @param  array $options Associative array of options
	 * @throws Zend_Cache_Exception
	 * @return void
	 */
	public function __construct(array $options = array()) {
		while ( list ( $name, $value ) = each ( $options ) ) {
			$this->setOption ( $name, $value );
		}
		if (! isset ( $this->_specificOptions ['master_files'] )) {
			Zend_Cache::throwException ( 'master_files option must be set' );
		}
	}
	
	/**
	 * Change the master_files option
	 *
	 * @param array $masterFiles the complete paths and name of the master files
	 */
	public function setMasterFiles(array $masterFiles) {
		$this->_specificOptions ['master_file'] = null; // to keep a compatibility
		$this->_specificOptions ['master_files'] = null;
		$this->_masterFile_mtimes = array ();
		
		clearstatcache ();
		$i = 0;
		foreach ( $masterFiles as $masterFile ) {
			if (file_exists ( $masterFile )) {
				$mtime = filemtime ( $masterFile );
			} else {
				$mtime = false;
			}
			
			if (! $this->_specificOptions ['ignore_missing_master_files'] && ! $mtime) {
				Zend_Cache::throwException ( 'Unable to read master_file : ' . $masterFile );
			}
			
			$this->_masterFile_mtimes [$i] = $mtime;
			$this->_specificOptions ['master_files'] [$i] = $masterFile;
			if ($i === 0) { // to keep a compatibility
				$this->_specificOptions ['master_file'] = $masterFile;
			}
			
			$i ++;
		}
	}
	
	/**
	 * Change the master_file option
	 *
	 * To keep the compatibility
	 *
	 * @deprecated
	 * @param string $masterFile the complete path and name of the master file
	 */
	public function setMasterFile($masterFile) {
		$this->setMasterFiles ( array ($masterFile ) );
	}
	
	/**
	 * Public frontend to set an option
	 *
	 * Just a wrapper to get a specific behaviour for master_file
	 *
	 * @param  string $name  Name of the option
	 * @param  mixed  $value Value of the option
	 * @throws Zend_Cache_Exception
	 * @return void
	 */
	public function setOption($name, $value) {
		if ($name == 'master_file') {
			$this->setMasterFile ( $value );
		} else if ($name == 'master_files') {
			$this->setMasterFiles ( $value );
		} else {
			parent::setOption ( $name, $value );
		}
	}
	
	/**
	 * Test if a cache is available for the given id and (if yes) return it (false else)
	 *
	 * @param  string  $id                     Cache id
	 * @param  boolean $doNotTestCacheValidity If set to true, the cache validity won't be tested
	 * @param  boolean $doNotUnserialize       Do not serialize (even if automatic_serialization is true) => for internal use
	 * @return mixed|false Cached datas
	 */
	public function load($id, $doNotTestCacheValidity = false, $doNotUnserialize = false) {
		if (! $doNotTestCacheValidity) {
			if ($this->test ( $id )) {
				return parent::load ( $id, true, $doNotUnserialize );
			}
			return false;
		}
		return parent::load ( $id, true, $doNotUnserialize );
	}
	
	/**
	 * Test if a cache is available for the given id
	 *
	 * @param  string $id Cache id
	 * @return int|false Last modified time of cache entry if it is available, false otherwise
	 */
	public function test($id) {
		$lastModified = parent::test ( $id );
		if ($lastModified) {
			if ($this->_specificOptions ['master_files_mode'] == self::MODE_AND) {
				// MODE_AND
				foreach ( $this->_masterFile_mtimes as $masterFileMTime ) {
					if ($masterFileMTime) {
						if ($lastModified > $masterFileMTime) {
							return $lastModified;
						}
					}
				}
			} else {
				// MODE_OR
				$res = true;
				foreach ( $this->_masterFile_mtimes as $masterFileMTime ) {
					if ($masterFileMTime) {
						if ($lastModified <= $masterFileMTime) {
							return false;
						}
					}
				}
				return $lastModified;
			}
		}
		return false;
	}

}

